In an experiment, the length of an object is measured to be 6.50 cm. This measured value can be written as 0.0650 m.The number of significant figures on 0.0650m is
- 3
- 4
- 2
- 5
The Correct Option is A
Solution and Explanation
The correct answer is option (A): 3
Significant figures are the numbers of digit in which a value in which a value of physical quantity can be expressed properly.
The following rules must be known to find the number of sig. value
(1) All non-zero numbers are significant.
(2) All zeros are significant except if they lie within two sig. numbers or placed at the end.
(3) In exponential notation, the numerical is the number of sig. figures.
So, here the given number is 0.0650 where “0.0” is insignificant and 650 is significant.
Hence, the number of insignificant figures is 3.
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Concepts Used:
Units and Measurement
Unit:
A unit of a physical quantity is an arbitrarily chosen standard that is broadly acknowledged by the society and in terms of which other quantities of similar nature may be measured.
Measurement:
The process of measurement is basically a comparison process. To measure a physical quantity, we have to find out how many times a standard amount of that physical quantity is present in the quantity being measured. The number thus obtained is known as the magnitude and the standard chosen is called the unit of the physical quantity.
Read More: Fundamental and Derived Units of Measurement
System of Units:
- CGS system
- FPS system
- MKS system
- SI units
Types of Units:
Fundamental Units -
The units defined for the fundamental quantities are called fundamental units.
Derived Units -
The units of all other physical quantities which are derived from the fundamental units are called the derived units.